Proto‐imogolite and the process of podzol formation: a critical note

SUMMARY The presence of imogolite or other poorly crystalline aluminosilicates in the lower B horizons of podzols can be explained by neoformation from silica in the percolating soil solution and aluminium species liberated from their organic bond by activity of micro‐organisms. There are physicochemical arguments refuting the alternative concept that iron and aluminium are transported down the profile as short range order aluminosilicates such as proto‐imogolite which would thus play an important role in podzol formation. There is ample evidence to attribute the mobilization, translocation and precipitation of sesquioxides to complexing organic compounds.